Dear Gigi,

I have begun to analyze your report and find something that does not seem 
logical according to my understanding of heat flow.  On your figure A2 I see 
that you have overlaid your simulation results upon Jed's figure.  The 
correspondence between the curves is remarkable and you should be commended for 
your work.

The issue that I need to resolve is that the delta temperature between the 
Dewar and ambient is actually increasing during this time.  Also, the delta for 
the reactor is becoming less with time as I was expecting.  In order for the 
temperature delta to increase you would have to supply some form of heat power 
to that device.  The model that you are using is extremely simple and certainly 
does not suggest that anything more complex would be happening.

How do you explain that the delta is increasing?  Is there some process that is 
supplying extra power into the Dewar once the pump is turned off?

Regards,

Dave

 

 

 

-----Original Message-----
From: Jed Rothwell <jedrothw...@gmail.com>
To: vortex-l <vortex-l@eskimo.com>
Sent: Tue, Jan 13, 2015 2:06 pm
Subject: Re: [Vo]:"Report on Mizuno's Adiabatic Calorimetry" revised



Gigi DiMarco <gdmgdms...@gmail.com> wrote:

 



The refrigerator example is quite evident, but is unfit to our situation, by 
various causes. The main one is that there you have an abrupt change of air 
temperature, while in the 18h test the air temperature is falling at a modest 
rate of 0,36 °C/h that is very simple to follow for the calorimeter.






No, it isn't. That is why a gap opens between the room temperature and the 
calorimeter, and the gap persists until early morning.


 




If from now on the losses are equal to the pump power, since you have


Loss = K * deltaT    and  PumpPower = loss = constant

and since K is valid over a broad range of deltaT you should have a constant 
deltaT.





No, it isn't. See Newton's law of cooling.


 



So going back to the plots in the missing file you considered only the first 
1.5 hour only because just after the ambient temperature starts decreasing. 
What have it happened if the ambient did not change for 5-6 hours? Can you 
answer this question?




Yes, I can. If ambient stays stable, the reactor and water temperature will 
remain stable at 0.6 deg C above room 


 


 Where in the data do you see that 0.6 °C is the maximum?




It goes no higher after 1.4 hours. You can see this in other data sets as well, 
such as early in the morning with this data set. Whenever ambient remains 
stable for a few hours or more, the reactor temperature always settles 0.6 deg 
C warmer.






 


Please don't be contemptuous and dismissive; it is not the case. If someone 
does't understand calorimetry it is not me.





You do not understand Newton's law of cooling and you cannot tell the 
difference between ambient cooling and heat generation in a cell. In my 
opinion, you are terribly confused and totally unqualified to do calorimetry.


- Jed




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